Portable electric air pump



March 29, 1949. M. ROY

PbRTABLE ELECTRIC AIR PUMP Filed'Oct. 21, 1946 .ZZ/emar: @0126? Patented Mar. 29, 1949 UNITED STATES- PATENT OFFICE 2,465,554 PORTABLE ELECTRIC AIR PUMP Maurice Roy, La Reine, Quebec, Canada Application October 21, 194.6, Serial No. 704,577

3 Claims. 1

The present invention pertains to a novel portable electric air pump designed particularly, but not exclusively, for inflating the tires of motor vehicles.

The object of the invention is to provide a device that eliminates the necessity of the usual stationary motor, compressor, installed hose and fixtures for inflating tires. Instead, the device of the invention may be carried to the tire and plugged into an electric outlet for operating the motor and compressor thereof. Another object of the invention is to provide a portable device that is self-contained and may be used for pumping or spraying other fluids after a simple adaptation for the latter purpose.

In the accomplishment of these objects, the device comprises a housing that is preferably elongated and shaped at one end as a nozzle, somewhat after the fashion of portable fluid ejecting guns. An electric motor is mounted in the opposite end of the housing and equipped with a conductor and plug. The motor drives a cam which in turn reciprocates a piston rod. The latter carries a piston mounted in the pump cylinder.

The pump or compressor is preferably in the form of a double acting unit, and accordingly the cylinder is provided at each side of the piston with an inwardly opening check valve and an outwardly opening check valve. The inwardly opening valves constitute the intakes, and the outwardly opening valves are connected to a discharge line which extends to the tip of the nozzle. The tip is suitably adapted to be attached to a tire valve when the device is to be used for inflating tires. For other purposes the various connections are readily adapted.

The invention also includes a system for cooling the internal mechanism and comprises a fan mounted on the motor shaft for circulating air through vents provided in the ends of the housing.

The invention is fully disclosed by way of example in the following description and in the accompanying drawings in which:

Figure 1 is a longitudinal section of the fan, and

Figure 2 is a section on the line 2-2 of Figure 1.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

In Figure 1 is shown an elongated and substantially cylindrical housing I terminating at one end in a nozzle 2 and having at the other end cross bearings indicated by the numeral 3. The tip of the nozzle 2 is reduced at 4 or otherwise formed to fit on a tire valve, for example.

In the housing I are mounted cross walls or partitions 5, 6 and 1 for supporting the various parts as will presently be shown. These members are secured by countersunk screws 8 or other equivalent means. Between the closed end 3 of the housing and the first partition 5 is mounted an electric motor 9 having its shaft 10 journalled in these parts. Adjacent to the end 3, the shaft H3 carries a fan H for cooling the motor and other mechanism. A conductor 12 controlled by a switch l2 extends from the motor to the end wall 3 and is fitted with a p outlet.

Between the partitions 5 and 6 is journalled a countershaft I4 carrying a cylinder H5 in which is formed a cam groove 16. The shaft I4 is driven from the shaft It] through gears I! as shown more clearly in Figure 2'. In the partitions 5 and 6 is slidably mounted a piston rod l8 on which is fixed a finger l9 extending into the cam groove l6. Thus, as the cam cylinder 15 is rotated from the motor, the finger l9 and rod l8 are reciprocated to actuate a piston in a pump as will presently be shown.

In the partition 'I is mounted a pump cylinder 20 which is co-axial with the rod I8 and has one end fitted against the partition 6. The rod I8 carries a piston 2| that works in the cylinder. The cylinder is valved for double action. At one side of the piston is an inwardly opening check valve 22 and an outwardly opening check valve 23. A discharge line 24 extends from the valve 23 to the tip 4 of the nozzle. At the other side of the piston, the cylinder is fitted with an inwardly opening check valve 25 and an outwardly opening check valve 26, the latter being connected by a branch line 21 into the line 24.

In the operation of the device, the piston 2| is obviously reciprocated with the rod l8 which is actuated in the manner already described. When the piston moves in the direction of the arrow in Figure 1, the valve 22 is closed and air is expelled through the valve 23 into the line 24. At the same time, at the other side of the piston, the valve 25 opens to admit air into the cylinder, and the valve 26 closes. 0n the reverse stroke, the positions of the respective valves are reversed. Valves '23 and 25 close, and valves 22 and 26 open. Consequently air is admitted at one end of the cylinder through valve 22 and expelled from the other side of the piston through valve 26 into the branch line 21 and main line 24. There is thus provided a double acting pump l3 adapted to be inserted in a suitable,

that furnishes a continuous flow of air to the tip 4 of the nozzle. Branch line 21 is provided with a gage 28 to indicate air pressure.

As already indicated, the latter may be connected to a tire valve to inflate the tire. The device is portable and self-contained, so that tires may be inflated without requiring the conventional installed compressor and hose. In fact, the device may be carried on the vehicle and driven from the battery of the vehicle,

A shell 29 may be fitted over the end '3 and formed with apertures or vents 30 with fins 3! adjacent thereto. Similarly, at the opposite end of the device, the nozzle 2 is formed with vents 32 and inwardly directed fins 33 adjacent thereto, The fan I I circulates air through the "vents from one side of the device to the other, and the fins aid in transferring heat from the walls of the device to the air stream,

The device may also be used for pumping or spraying liquids by connecting the intake valves 22 and 25 to the supply receptacle andadapting the tip 4 for the character of discharge described.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention as indicated by the appended claims.

What I claim as my invention is:

1. A portable pump comprising a housing, a motor mounted therein, a pump cylinder in said housing, a piston in said cylinder, a piston rod extending from said piston through an end oi said cylinder, a grooved cam journallecl in said housing and geared to said motor, a finger extending rigidly .from said rod into the groove of said cam, fluid intake means connected to said cylinder, and a discharge line extending from said cylinder to a wall of said housing.

2. A portable pump comprising a housing, a motor mounted therein, a pump cylinder in said housing, a piston in said cylinder, a piston rod extending from said piston through an end of said cylinder, a grooved cam journalled in said housing and geared to said motor, a finger extending rigidly from said rod into the groove of said cam, inwardly opening check valves connected to saidcylinder at opposite sides of said piston, outwardly opening check valves connected to said cylinder "at opposite sides of said piston,

and a discharge line extending from the last named valves to a wall of said housing.

3. A portable pump comprising a housing, a motor mounted therein, a pump cylinder in said housing, a piston in said cylinder, a piston rod extending from said piston through an end of said cylinder, a cam geared to said motor, a member extending from said rod into engagement with said cam to be reciprocated by the latter, fluid intake means connected to said cylinder, an end of said housing being formed as a nozzle, and a discharge line extending from said cylinder to said nozzle.

MAURICE ROY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number N m ate 793,465 Olson -i June'2'7, 1905 1,176,843 Lukomski ar, 2a, 1916. 1,1 7,0 1 Blac e un 11 19 "6 1,555,287 Howe Sept. 29, 1925 2,372,058 Campbell Mar. 20., 1945,- 

